1. Field of the Invention
The invention relates to a course evaluation apparatus and a course evaluation method that perform a course evaluation for a movable body such as a vehicle.
2. Description of the Related Art
Japanese Patent Application Publication No. 2007-230454 (JP-A-2007-230454) describes an apparatus that evaluates a course for a movable body. The apparatus evaluates a course along which a specific object among a plurality of objects may move. The apparatus generates trajectories indicating time-dependent changes in positions at which the plurality of objects may be located, in a time-space constituted by time and space. Then, the apparatus estimates courses along which the plurality of objects may move, using the trajectories. Then, the apparatus quantitatively calculates the degree of interference between the course along which the specific object may move and the courses along which the other objects may move, using the results of the estimation.
The apparatus evaluates the courses with respect to one evaluation criterion, that is, the degree of interference (possibility of collision). However, the courses may be evaluated with respect to other evaluation criteria such as the efficiency of movement (degree of smoothness of movement), in addition to the degree of interference. For example, a plurality of estimated courses may be generated, the estimated courses may be evaluated with respect to two evaluation criteria, that is, the degree of interference and the efficiency of movement, and the optimum estimated course may be selected.
However, in this case, there is a possibility that one estimated course meets the evaluation criterion of the degree of interference, but does not meet the evaluation criterion of the efficiency of movement, and the other estimated course meets the evaluation criterion of the efficiency of movement, but does not meet the evaluation criterion of the degree of interference. As a result, it may not be possible to find an appropriate estimated course. That is, it may not be possible to select an appropriate course.